The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 27, 2011
Filed:
Feb. 13, 2009
Hiroko Yamazaki, Kanagawa, JP;
Satoshi Seo, Kanagawa, JP;
Hiroko Yamazaki, Kanagawa, JP;
Satoshi Seo, Kanagawa, JP;
Semiconductor Energy Laboratory Co., Ltd., Kanagawa-ken, JP;
Abstract
The present invention provides a white organic light-emitting element high in the emission efficiency. In particular, the invention provides a white organic light-emitting element that has an emission spectrum having peaks in the respective wavelength regions of red color, green color and blue color and is high in the emission efficiency. Since a spectrum region lowest in the emission efficiency is a red region, by introducing a reddish phosphorescent material, a highly efficient white organic light-emitting element is obtained. At this time, in order to inhibit the reddish phosphorescent material from singularly emitting, as shown in FIG., a distance between a second emission regionwhere a reddish phosphorescent materialis a luminescent material and a first emission regionthat exhibits emission in a shorter wavelength side than the second emission region is separated. In a configuration shown in FIG., it is preferable to use an electron transport material in a layerbetween the first emission region and the second emission region and more preferable to use a hole block material.